In summer 1994, Michael Doall and Sean Colin researched for two months in the Strickler Lab. At that time they both were graduate students in the Jeannette Yen laboratory at SUNY Stony Brook. From the Long Island Sound they brought with them adult Temora longicornis and algae for food. In Milwaukee they added the animals to the 3D experimental set-up and noted right away that males started to chase females. Questions then arised:
(1) Can males detect females at a distance?
(2) Do males follow "tracks" left behind by the swimming females?
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Let's look at the observation to the right:
* The male starts in the mid of the X/Y plane and its track is represented by a light blue line.
* The female starts higher up and more in the corner (thicker blue line).
* Both swim with a speed of about 10 mm/s (blue color).
* The male crosses her "track".
* He then follows her "track".
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The change of color from blue to red and brown means an increase of swimming speed to about 30 to 40 mm/s
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This means that as soon as the male encountered the "track" of the female he not only follows it but he does so at a much higher speed. (Well, how else could he catch up with her not having the information how and where to cut corners?)
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The next question would be: what was the signal informing the male where the female went and in which direction? Is it a chemical trail, like in ants? Is it the disturbance of the fluid the female created when she swam through the volume of water?
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